Porous Material for Use as Implant, Bone Replacement and in General as Material

ABSTRACT

Implants and methods for producing same are described, the implants featuring an adjustable porous shell, the inside being continuously interconnectingly adjustably porous and which can be sintered net shaped; these implants exhibit a high compression stability and show, when being combined with filler materials with or without active agents, different chemical, physical-mechanical, biomechanical or also pharmacological properties. The essential features of the manufacturing process are described in FIG. ( 1 ) and comprise expandable shaping elements, deformable elastic tools, the application of defined negative pressures, temperatures during defined application periods in combination with combined materials, which can be separated from each other physically, chemically or mechanically and removed.

BACKGROUND OF THE INVENTION

In surgery of the musculuskeletal system, there has always been a needto re-fill bone defects after fractures, the removal of tumors, a lossof bone substance after inflammations or in connection with bone cysts,with bone material or a substitute material similar to bone. For thispurpose, partially also bovine substitute material was used [Tröster SD1993: Die Hydroxylapatitkeramik Endobon®]. An alternative possibilityfor therapy for bone defects, in: Venbrocks R, Salis G of (publisher):Jahrbuch der Orthopädie, pp 231-246, Zülpich: Biermann] or material ofcoral reefs [Irwin R B, Bernhard M, Biddinger A (2001) Corallinehydroxyapatite as bone substitute in orthopaedic oncology. Am J Orthop30:544-550], processed in laboratories (replaminiform processes) andinserted. Both materials have the drawback that they are biological andtherewith directed structures, which can no longer be influenced andwhich can hardly be produced in a standardized manner. Both materialsincorporate the anisotropy in structure and properties of a grownbiological structure and are, in most cases, too stiff. A method formanufacturing such biological substitute materials is described inDE-A-3903695. Synthetic substitute materials can be manufactured frompure raw materials, however, lack a regular structure being similar tothe bone; such a synthetic material is the foamed Ceros®; said materialslack a bony growing through, since the pores are mostly closed[Dingeldein E and H Wahlig (1992) FluoreszenzmikroskopischeUntersuchungen zur knöchernen Integration von Kalziumphosphatkeramiken.In: Merck Biomaterialien (publisher) Endobon® and DBCS®, Damstadt:Merck].

In the published documents DPA 2242867 and U.S. Pat. No. 3,899,556, amethod comprising a pre-formed shaping framing is described, featuring adense filling of balls, in which the shaping elements are poured with asolvent and shall be glued together in this way; however, with such amethod, no regular, porous, interconnecting material can be produced ina standardized way; the conglutinations were too irregular and thesolving process was not controllable enough. In EP 0553167 and EP0204786, the problem was partially solved, in that deformable shapingelements were pressed on each other in contact by applying a pressureand were surrounded by a frame-forming mass in this state, whichsubsequently cured and was freed from the shaping elements chemically orthermally. The implants produced in this way showed beautiful and nearlyregular interconnections in the half which faced the pressurization,however, in the other half, numerous closed pores were formed.Deformable and only partially elastic shaping elements dampen theapplied force and the deforming effect is wears out by the dampening,such that no regular and continuous interconnection can be achieved. Bypure chance, a method was now found which avoids said phenomena andachieves a completely regular deformation of all shaping elementsassociated with this process. Said method is rather simple and thereforevery economic and completely reproducible.

DESCRIPTION OF THE INVENTION

The use of a negative pressure applied on the shaping elementssurprisingly led to a perfect result. Herein, the shaping elements beingfilled loosely into a tool are either charged with a defined negativepressure in a vacuum-sealed system before the filling and subsequentlythe frame-forming mass is suctioned and cured by applying the definednegative pressure at a defined temperature over a defined period oftime, or are charged with the defined negative pressure together withthe frame material after the filling and simultaneously cooled-down,e.g. by a metal setting plate.

This nearly even simpler arrangement led to further standardized resultsand comprises the following steps: the loose fill of shaping elementswas moulded in with the structure-forming framing mass and the closedcontainer, which was not vacuum-sealed, was exposed to a definednegative pressure at a defined temperature and over a defined period oftime in a sealed container charged with a negative pressure, andsimultaneously cooled-down through the setting plate. The simplehandling of this process made the result highly reproducible.

However, also this result could be further enhanced by chance due to aninitially unimpressive change, in particular in view of the adjustableporosity of the surface: If one used a deformable silicone mould insteadof a solid metallic tool, this resulted in the fact that the implant,dependent on the applied negative pressure, had a continuous porosityextending up to the surface, said porosity being adjustable through theamount of negative pressure on the one side and the E-module of the toolon the other side. Said method enables to achieve a continuous porosityeven if the shaping elements were not expandable, e.g. notair-containing, but were e.g. sugar balls.

As the shaping elements in this method, preferably expandablepolystyrene balls (EPS) are used, e.g. Styrofoam® F414, which is foamedwith pentane as an expanding agent. Upon applying a negative pressure,these balls expand very fast and increase in volume. In this way, thecontact bridge between the balls becomes wider and therewith determinesthe diameter of the interconnecting passages up to the surface; uponusing of a silicone tool, the balls squeeze into the silicone wall and,furthermore, the negative pressure draws the deformable wall over theball surface into the implant.

Foamed materials to be used as shaping materials are preferablyemployed, also those to which an expanding agent was added, which isactivated at a specific temperature or under specific preconditions. Anespecially preferred material is Styrofoam® F414, having a preferredvolumetric weight of the foamed polystyrene between 17 g/l and 70 g/l,preferably approx. 20 g/l to 35 g/l. The grain size distribution of thefoamed material lies between 200 μm and 15 mm, often used are the sizesbetween 1000 μm and 3000 μm. In order to determine the expansion and thedeformability of the individual shaping materials, experiments wereperformed to determine the parameters in a simple manner, saidparameters being required for the standardization of the method. Forthis purpose, different shaping elements having different volumetricweights, e.g. differently foamed polystyrene balls having differentdiameters, were filled into a cylinder with movable, vacuum-sealedabutting pistons up to a defined height of 84.3 mm and exposed to adefined vacuum; from the change of the original height in dependency ofthe applied negative pressure, quantities were determined whichrepresent an initial reduction of volume by removing of air between theshaping elements, followed by an expansion of volume which wasadjustable to the former initial length by applying a force F, measuredin N, and represented the expansion pressure of the air in the shapingelements. Depending on the time period, the force slowly decreased,which could be explained by the bursting of the air bubbles in theplastics. Based on this phenomenon, the defined time periods for thecharging with negative pressure were determined.

Pressures between 150 mbar and 800 mbar, preferably approx. 300 mbar to500 mbar, over a time period of 15 minutes, applied on aphosphorate-agar agar mixture, at a temperature of the implant of 4 to12° C., showed especially advantageous results in view of the outsideporosity and the inner interconnections.

As deformable moulds, in particular silicones having a shore hardnessbelow 25 shore, preferably below 18-20 shore, used in casting orinjection die casting methods are suited. However, all plastically orelastically deformable materials can be used, the E-module of which liesclearly below that of the shaping elements. Correspondingly, the toolscan be cast, but also be manufactures in mass production with injectionmoulding methods. Examples for plastically deformable tools are toolsmade of Styrofoam® having different density, examples for elasticallydeformable tools are the aforementioned silicones, wherein also foamedsilicones can be used. The expansion pressure of said materials invacuum adds in its effect to that of the expandable shaping elements.

As castable material for the framing material, a mixture ofhydroxylapatite (HA) or triphosphorate (TCP) and an agar agar solutionin a ratio of 10 g powder/7 ml to 25 ml solution, corresponding to aratio of 1.4 to 0.4, is preferably used, ideal would be preparations inwhich the mixing ratio powder/solution corresponds to 0.45 to 0.48, e.g.1600 g HA and 3500 ml solution.

Depending on the composition, the shrinking factor can already becalculated on the basis of the preparation: same lies between 0.95 to2.9, preferably between 1.75 and 2.15, for a HA-agar agar mixturecapable of flowing, which is filled at a temperature of 60° C., at aratio of 16 g/35 ml of a 1.7% agar agar solution at exactly 1.91. Uponthese two preconditions, expandable shaping elements, a deformablesilicone mould and an exact preparation with defined shrinking, veryprecise implants could be sintered net shaped, without the necessity ofa post-processing.

The definite design multiplied with the shrinking factor leads e.g. toan implant body in plastics or any other material being easilyprocessable in a CAD/CAM process, which is re-cast with a castablesilicone in an original mould up to the top edge. After curing of thesilicone, the shaping body can be mechanically removed easily, thesilicone mould is perforated several times at the bottom and issubsequently filled with polystyrene balls of a desired size, the closedwith a silicone lid having venting holes and filled in a filling mouldwith e.g. the ceramic mass. Immediately after the filling, the tool isas a whole charged with a negative pressure in an exsiccator and cooleddown to 4-12° C., e.g. through the setting plate. After curing of theceramic mass, the tool can be de-assembled and the green body can beeasily removed. In an acetone washing, the Styrofoam is dissolved fromthe ceramic Styrofoam® implant, the ceramic is dehydrated in steps of70/80/90 and 100% acetone and subsequently stepwise dried in air bycooling (cool drying). The result is documented every hour by means of aprecision scale; if no further loss of weight in the air begins to showand the curve of weight remains to be linearly unchanged, the implant isdried for 24 hours in the exsiccator by adding P₂O₅ in a vacuum of150-250 mbar absolute pressure and subsequently burnt at 1300° C. in thesintering furnace. This results in an open pore implant being absolutelytrue to size, having a clearly higher strength compared to mechanicallypost-processed bone substitute material cylinders or cubes (Draenert etal. 2001: Synthetische Knochenersatzstoffe auf HA und TCP-Basis TraumaBerufskrh 3:293-300 Heidelberg New York Berlin Tokyo: Springer), saidstrength being able to be further increased by outside structuring, e.g.rings, contractions, massive edges etc.

EXAMPLE (1)

Styrofoam® balls having a diameter of 12 mm are immersed and introducedinto a cup in a cylindrical container having a perforated bottom withboreholes of 10-11 mm in diameter and a fixable lid seated flush on theballs and having the same boreholes, said cup being filled with hot waxhaving a temperature of 90° C. and being taken from the heating furnacefor this purpose. The container with the Styrofoam® balls in its outerdiameter hereby fits flush into the cylindrical wax container which hasa removable bottom. After curing of the wax at room temperature, thebottom of the wax container is removed and the Styrofoam® container ispressed out. The Styrofoam® container is also freed from its bottom andlid and the wax-Styrofoam® cylinder is pressed out and freed from theStyrofoam® in an acetone washing. After drying in air, the resultingcontinuous, interconnecting, porous wax framing is inserted into afilling container receiving same in a flush manner. The fillingcontainer has a filler neck with perforations at the bottom of thecontainer and may also contain a screen which is required for suctioningsmaller Styrofoam® balls, furthermore, it is provided with a lid havingventing boreholes, e. g. having a diameter of 1.5 to 2.5 mm. Styrofoam®balls having a diameter of e.g. 600-1200 μm are suctioned into the waxframing, wherein a screen having a mesh size of 400 μm is arrangedupstream. The cavity system of the wax framing is completely filled withthe smaller Styrofoam® balls and is then closed with a lid. Thecontainer is now filled with a ceramic mass, wherein the mass issuctioned through the venting holes through the filler neck or is filledwithout pressure simply through the filler neck. If the ceramic massprotrudes through the venting holes of the lid, the mould is filled andis put into an exsiccator together with the tool and charged with anegative pressure of 500-600 mbar for 15 minutes and cooled-down duringthis time period by the metallic setting plate. The thus curedwax-ceramic-Styrofoam® block is subsequently freed from the Styrofoam®in the acetone washing, dried in air and sintered together with the waxin a furnace at 1300° C. This results in completely isolated, at theoutside continuously porous and at the inside completely interconnectedporous balls having a diameter of 6 mm. Due to the shrinking of thematrix material, completely separated balls are formed.

EXAMPLE (2)

Instead of individual porous balls, an interesting material may beproduced, which corresponds to a negative print of the marrow combs, anda ball conglomerate having gaps between the porous balls for theregrowing of bone trabeculae and wide connecting bridges, whichcorrespond to the contact points of the balls: The steps correspond toexample 1, however, the wax-Styrofoam® framing is exposed to a definednegative pressure of e.g. 600 mbar during the curing in the excissator.The following expansion of the Styrofoam® balls results in wider bridgesand thicker connecting arms between the balls. After curing of thewax-Styrofoam® framing, the Styrofoam® is removed. The following stepscorrespond to example 1, with suctioning of the smaller Styrofoam®balls, filling with ceramic mass, post-evacuating by cooling andsubsequent dissolving of the shaping elements in acetone; contrary toexample 1, the cool drying step follows: in steps of 2 hours each, in70/80/90 and 3×100% acetone, it is cooled in air in steps in thefreezer, at 4-12° C. increasingly in e.g. 4 steps of 3 hours each untilroom temperature is reached and subsequently dehydration in theexsiccator by using P₂O₅ and a vacuum of about 150 mbar absolutepressure during 24 hours. Upon such a procedure, wide bridges betweenthe porous balls remain and the wax framing may be burnt at e.g. 1300°C. together with the ceramic inlet; the wax may also be melt off in theheat furnace at 90° C.; a precondition is that the ceramic mass isalready dried in air. The result is a perfect framing made ofinterrelated, in the inside perfectly interconnected porous balls with acontinuous porous surface and an astonishing high compression strength.Same lies between 4-12 Mpa, depending on the size of the balls.

EXAMPLE (3)

The production of a cube true in size, having an edge length of 15 mmand an open porosity over all surfaces: Upon a matrix mass of 16/35HA/agar agar suspension of 1.7%, a shrinking factor of 1.91 iscalculated and in a CAD/CAM process, a cube made of POM having an edgelength of 28.65 mm is produced. Since the cube shall achieve a highstrength of 4-6 Mpa, the edges are not rounded. The cube is put into amoulding tool and poured with self-curing silicone until its top edge.After 24 hours, the cube is removed mechanically and the silicone toolis inserted into a filling tool, the bottom of which consists inside ofa perforated silicone bottom and is covered in a flush manner with asilicone lid having venting holes after having been filled with 1200 μmsized Styrofoam® balls. After the tool was closed with a screw caphaving venting holes, it is filled with a ceramic mass; subsequently,the charging with negative pressure of 500 mbar for 15 minutes uponsimultaneous cooling occurs in the excissator on a metallic and coolablesetting plate. After that, the tool is de-assembled and theceramic-Styrofoam® cube is carefully taken out mechanically and freedfrom the shaping elements in the acetone washing. For a crack-freedrying, the cool dehydrating follows, as described in examples 1 and 2,and subsequently, the cube is sintered in the furnace at about 1300° C.The result is a cube true in size and having a very high compressivestrength, with open porosity over all surfaces and a continuouslyinterconnecting porosity of the inner structure and reinforced edgesmade of solid ceramics.

In FIG. 1, a simple vacuum chamber in the form of an exsiccator (10) isdescribed, comprising a venting valve (13) and a tap for attaching apipe leading to the vacuum pump (12) and a metallic cooling plate (11)having a filling tool (1) arranged on the cooling plate and having adeformable tool received in a flush manner and consisting of threeparts, a body (2), a lid (7) with perforations (4) and a bottom (8) withperforations (5) for filling e.g. a ceramic mass.

In FIGS. 2 a and 2 b, ceramic implants according to claim 1 are shown(20), once in a plan view and in FIG. 2 b as a sectional view. The planview on the ball shell shows the open porosity (22) and the rough shell(21). In the sectional view, the interconnecting pore structure (23) isshown.

In FIG. 3, an implant according to claims 1 to 3 is shown as a bonedowel (30), e.g. for re-fixing a ligament in case of a cruciate ligamentsubstitute across the outside of the dowel, which comprises horizontal(31) contractions, which can be arranged preferably also helical, andwhich has an outer shell interrupted by pores (32) across the completesurface.

In FIG. 4, a light ceramic implant (40) is shown, sintered net shaped,having an open porosity across the complete surface (43), comprisingcrossing depressions or channels (41, 42), in which the eye muscles canbe sewed, which is used as a part of an artificial eye.

FIG. 5 shows a ball conglomerate (50) consisting of solid balls (51),which may however also consist of the elements of FIG. 2 and featureswide bridges (52) between the ball elements and regular ball intervals(53).

1. An implant body comprising: a porous implant body including a shellhaving a surface, penetrated by pores having an adjustable diameter, andfurther including an inner structure comprising a cavity or aconglomerate of cavities surrounded by ball-shaped shells, and shellframing that encompasses a connected cavity system made of hollow ballsor ball-shaped cavities, which is continuously interconnected by meansof a pore system in the shell framing, the pore system having anadjustable diameter.
 2. The implant body of claim 1, shaped as a cuboidor cube, cylinder, cone or disc, half shell or halfball, ball segment,ball cut, wedge or ring or disc ring, pyramid or frustrum of pyramid,spiral or screw.
 3. The implant body of claim 1, configured such thatthe outer shell is structured in the shape of circular or radial,longitudinal, oblique or helical, parallel or crossing extendingcontractions, channels or bulges or both, singular or in a pluralitythereof, or in the shape of single or plural elevations, recesses, orpins.
 4. The implant body of claim, configured such that the innerstructure corresponds to a bowl-shaped sponge bone or cancellous bone.5. The implant body of claim 1, configured such that the pore of theouter shell has a diameter smaller than the diameter of the cavityconnected therewith, namely in the ratio of 1:5 to 1:1.5, in average 1:2to 1:3.
 6. The implant body of claim 1, preferably having the shape ofporous balls or ball-shaped structures of a size between 0.8 mm and 12mm in diameter, in average between 1-2 mm and 3-6 mm in diameter, and aninterconnected inner pore system having diameters of the pores between80 mm and 1500 mm, preferably 150 mm to 600 mm.
 7. The implant body ofclaim 1, configured such that a conglomerate of individual implants isformed, preferably of ball shape, being connected to each other throughbridges having adjustable widths and encompassing a cavity system beinginterrelated as such, which enables that the preferably ball-shapedimplant bodies may be encompassed by the bones in a manner that aphysiological sponge bone framing is generated, the passages of whichthrough the connecting bridges of the implant bodies are predetermined.8. The implant body of claim 1, configured such that the frame materialis a phosphorite, especially tri-calciumphosphate (TCP) ortetra-calciumphosphate, a hydroxyapatite, a calcium carbonate orcalcium-sulfate-composition, or also an aluminium oxide ceramic, acollagen, a polyaminoacid or any other absorbable polymer, but also anacrylate or derivate thereof, a polymethyl-methacrylate or a copolymerthereof, with or without phosphate, calcium sulphate or calciumcarbonate as filler material, or a metal, preferably a CoCrMo alloy,titanium or tantalum or an alloy thereof.
 9. The implant body of claim1, configured such that the cavity system is filled or coated completelyor partially with an absorbable or non-absorbable organic or inorganicfiller material, having dampening or reinforcing properties, in a mannerthat the inner filling is restricted to the inside of the implant bodyor completely fills same, but does not extend beyond the outer shell, orregularly or irregularly wells out of the pores of the outer shell andforms drop-shaped and/or ball-shaped or similarly shaped elevations overthe outer shell, to prevent them completely or nearly completely frombeing regularly or irregularly distributed over the surface,micro-movements of plural identical or similar implant bodies, forexample in one fill.
 10. The implant body of claim 9, configured suchthat as the filler material, an absorbable polymer, e. g. poly-aminoacid, a polylactide, polyglactine, glycoside or similar material,generally polyacetals, poly-acid amides or polyester, but also notabsorbable polymers such as polymethylmethacrylate or similar polymers,agarose gels or mixtures of agarose gels and a calciumphosphate or acalcium carbonate is used.
 11. The implant body of claim 1, configuredsuch that exclusively the center or the center axis or the cavitiesalong the center axis, interrelated or individual distributed cavitiesor groups of cavities are filled with a material according to claims 9and 10, said material comprising an active agent which is released fastor slowly, momentary or retarded and centrifugally distributes bydiffusion over the free implant surface.
 12. The implant body of claim1, configured such that said implant body includes at least one of anactive agent, a growth factor, a bone morphogenetic protein orcombinations thereof, or comprises an antibiotic or a hormone, animmunosuppressive drug, a zytostaticum or a mixture of growth factorsand an antibiotic or a combination of different agents.
 13. The implantbody of claim 12, configured such that Gentamycin, Clindamycin,Streptomycin or any other bacteriostatic or bactericide agent is used asthe antibiotic.
 14. The implant body of claim 1, configured such thatwide and narrow cavity systems are formed therein and that are arrangedinterrelated or interrupted, individual or in groups or also along anaxis and have interconnections of different widths, and that thecavities therewith can be filled more easily or less easily with fillermaterials or agents or combinations thereof.
 15. The implant body ofclaim 1, configured such that cavities of different size are structuredwith an interconnecting framing of an other absorbable or non-absorbablematerial, to include a large cavity having a shell-shaped wall made ofhydroxyapatite having a shell-shaped structured framing made of aneasily absorbable tri-calciumphosphate, wherein a continuously combinedimplant body comprising hydroxyapatite and tri-calciumphosphate isgenerated.
 16. An implant body of claim 1, having differing porosity,with or without filler material with or without an active agent,partially or completely filled in its cavity system.
 17. An implantdevice of claim 1, comprising a first implant body and a second implantbody mechanically inserted in said first implant body, said implantdevice composed of a porous or solid material with or without an activeagent and is either absorbable or non-absorbable.
 18. A method forproducing implants comprising the following steps: filling of shapingelements in a mould having a perforated bottom and lid, such that theshaping elements cannot fall out, by use of a filter grid, the bottomand lid being arranged relative to each other such that the shapingelements can be retained in close contact, intrusion of the mould withthe shaping elements being retained in shape into a key form, whichreceives the mould in a flush manner, filled with hot wax having amelting temperature between 60° C. and 90° C., as a rule 80° C., andcuring the wax, extracting the mould with the cured wax framing whichcomprises the shaping elements, and releasing and removing the shapingelements, such as by dissolving of air-containing polystyrene balls asthe shaping elements in acetone or dissolving of sugar balls in water ora similar removing of other physically or chemically removable shapingbodies, which does not affect wax framing, filling of the cavity systemgenerated with smaller shaping elements, e.g. sugar balls in a tricklingmethod with the help of a vibraxer or Styrofoam® balls in a suctionmethod comprising a suction means and a filter lid, in order to avoidthe sucking through of the shaping elements, filling of the remainingcavity system around the shaping elements with a liquid material, suchas including a mixture of agar agar and a calciumphosphate, astri-calciumphosphate or hydroxyapatite that use capable of flowing andcuring, such as polymethylmethacrylate (PMMA) or a copolymer thereof,solidifying the material being capable of flowing around the shapingelements in the wax framing, including cooling the agar/calciumphosphatemixture, or including self curing of a PMMA material and subsequentlyremoving of the shaping materials and removing of the wax framing by anappropriate method, including dissolving of sugar balls or salts beingcrystallized out from a PMMA frame in water, or dissolving ofair-containing polystyrene balls from an agar-calciumphosphate mixturein acetone and subsequently dissolving of the wax in an appropriatesolvent, including methyl cellulose solve acetate, or burning the waxduring the sintering in a sinter oven at temperatures between 900° C.and 1400° C.
 19. The method of claim 18 wherein: sugar or salt ballsbetween 300 mm and 15 mm are used as shaping elements and are dissolvedin water, and generated pores of the wax framing are filled with smallersugar or salt balls or air-containing polystyrene balls or other solubleair-containing or solid plastics which are subsequently surrounded by aframing material and subsequently again removed by means of water orsolvent or also heat.
 20. The method of claim 18 further comprising thestep of: air-containing shaping elements in the pores of the wax framingare exposed to a defined negative pressure in a temperate vacuum-sealedchamber and simultaneously cooled through a coolable setting plate,which results in the fact that the air-containing shaping elements, whenexpanding, displace soft wax into the ball clearances and wider contactbridges form between the elements, in particular in the boundary zonetowards the wax; the result thereof is, after suctioning of the framingmaterial and its curing, a porous structure of the implant body beingadjustable and having a definable interconnection and surface porositydue to the extent and duration of an acting vacuum.
 21. The method ofclaim 20 comprising the method steps described in claim 18, modified inthe following method step: air-containing shaping materials in the poresof the wax framing are surrounded by a framing material capable offlowing and completely filled; the implant body is subsequently placedinto a vacuum chamber, e. g. being tempered by a setting plate, togetherwith the air-containing, mostly foamed, shaping elements and the framingmaterial surrounding same, and charged with a defined negative pressureat 40 to 60° C., preferably 50° C.; in this context, it may also beadvantageous to operate with a cooled setting plate at 4° C. to 12° C.and increased negative pressure; same results in an expansion of theshaping elements and therefore directly influences the macro porosityand the passages (interconnections), but in particular also the surfacepores; the vacuum is exactly adjustable between 800 mbar and 150 mbarabsolute pressure and also adjustable temporally by a time switch, thetemperature in the container can be cooled-down fast, e.g. through asetting plate made of metal, such that the achieved result is retainedby the stiffening of the wax framing.
 22. The method of claim 18comprising the following modifications: filling of shaping materials,e.g. sugar balls, into a tool and injection-moulding of the ball fillingwith polystyrene foam, which cures subsequently, if necessary,intermediate storage in a defined humid chamber, a process which resultsin an etching of the sugar balls in the interface to the framingmaterial and in flowing bridges between the shaping elements, a processwhich can be distributed equally throughout the implant by a regularrelocating of the implant body, subsequently drying in a drying furnaceand removing of the shaping bodies with water or heat, without the stepof intermediate storage in a humid chamber, the removal of the shapingsugar or also salt elements, e.g. as balls, occurs immediately in thewater, filling the cavities in the foamed polystyrene framing withshaping elements and proceeding as described in claim
 18. 23. The methodof claim 18 comprising the following modification: as the framingmaterial, a castable and self-curing silicone is used, which issurrounded, e.g. by ⅘, by sugar balls or also air-containing polystyreneas shaping elements, or solid metal or plastic balls or shapingelements, which can be removed subsequently either chemically,physically or also carefully mechanically, the filling of the pores ofthe silicon framing with smaller shaping elements can be performed e.g.with sugar balls, but also with foamed polystyrene balls, which isperformed in the first case by a trickling method and in the second casepreferably by suctioning through a filter grid, in case the pores andgap system is, as described in claim 18, filled e.g. with anagar/hydroxyapatite mixture and subsequently exposed to a definednegative pressure in a vacuum chamber, passages and boundary porositiesare formed due to the deformability of the tools and the expansion ofthe shaping elements.
 24. The method for producing an implant bodyaccording to claim 1, comprising the steps of: the outer mould of theimplant body having definite masses is multiplied with a shrinkingfactor of the material of the supporting frame and producedmechanically, or by an impression method or by CAD/CAM, producing asilicon mould in a tool with silicone using a casting method, said mouldrepresenting the implant body except for the lid, filling the siliconetool with the shaping elements and closed with a silicone lid; Fillingthe tool through the lid with a malleable mass of the supporting frame,including a mixture of agar agar and hydroxyapatite; subsequently, thetool with the shaping elements, surrounded by the mass of the supportingframe, is charged with a negative pressure in a closed chamber andcooled-down, subsequently, the removal from the mould and the removal ofthe shaping elements, including the foamed polystyrene balls in acetoneoccurs, after the stepwise dehydration in the acetone, the implant bodyin the freezer is dried slowly in air and subsequently furtherdehydrated in the exsiccator by applying phosphorpentoxide, the thusdried implant body, e.g. consisting of an agar agar/hydroxyapatite oralso an agar agar/TCP mixture, is burnt in a sintering furnace; the thusgained porous implant body features a continuous porosity including itscomplete surface and is true to size and free of cracks.
 25. The methodof claim 24 for producing porous ball-shaped implant bodies according toclaim 1, comprising the following modifications: the silicone print isproduced by a monolayer of steel or polyamide balls which are moulded inby ⅘ and which are subsequently removed mechanically from the elasticmaterial, the resulting cavity system is filled with smaller shapingelements, e.g. foamed polystyrene balls, by using a filler tool having aperforated silicone bottom, and subsequently closed with a perforatedlid having a perforated silicone deposit; bottom and lid compriseboreholes for being filled with the framing mass or for venting, thetool is filled with the mass of the supporting frame, e.g. a mixture ofagar agar and HA or tri-calciumphosphate, subsequently charged withnegative pressure in a closed chamber and cooled-down, the thussolidified implant bodies are pushed carefully from the mould and theshaping elements are removed, e.g. the foamed polystyrene balls inacetone, dehydrated and subsequently burnt at 1000° C. to 1300° C., e.g. in a zirconium pot.
 26. Producing of an implant according to claim 1,as a result of the following method steps: producing an elastically orplastically deformable tool, e.g. with an injection moulding method,according to a CAD/CAM design or any other technical design, or with aprinting or casting method of a direct template, in any case inconsideration of the shrinking factor and configured such that it can befilled with shaping elements and closed again, e.g. as a sandwich or asa nearly closed body having an opening and a lid and venting means onthe opposite side; filling of the deformable tool with shaping elements,e.g. expandable polystyrene balls or directly with Styrofoam® balls, orother shaping materials in ball shape or any other shape, being easilyremovable, e.g. sugar or salt balls, gelatine or any other materialbeing easily removable; injecting into a filling tool, e.g. a main toolin an injection die casting machine, or an other filling device for theframing material; filling by injecting or suctioning of the framingmaterial with or without defined negative pressure; cooling of the tool,together with the implant, in the vacuum chamber by applying a definednegative pressure and over a defined period of time; removing theimplant, together with the shaping elements, and physically orchemically dissolving of the shaping elements; burning of an e.g.ceramic implant at 900° C. to 1400° C. in a sintering furnace.